quadruped; four-footed animal
A formal or technical term for any animal that walks on four legs. In everyday speech, 四足動物 (しそくどうぶつ) is more common.
I am studying the gait of quadrupeds.
Compound of 四 (four) + 足 (foot) + 獣 (beast). The reading is on'yomi, suggesting a Sino-Japanese coinage.